


Optimal Play

by maserspark



Category: Persona 3, Persona 4, Persona Series
Genre: Chess, Comedy, Family Bonding, Fluff, Fluff and Humor, Gen, Slice of Life
Language: English
Status: Completed
Published: 2018-05-21
Updated: 2018-05-21
Packaged: 2019-05-09 20:13:11
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,659
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14722838
Author URL: https://archiveofourown.org/users/maserspark/pseuds/maserspark
Summary: Ever have two computers play chess against each other?





	Optimal Play

An idea played out on a chessboard.

While cleaning, a set was found hidden away in the back of a closet. It was old, cheap, but usable. All the pieces were still there. The colors had faded, but they would still serve their sole purpose.

Within minutes, the two sisters sat across from each other, rigid as stone. Their minds played out thousands of moves in scant seconds.

It was, Yukari had to admit, one of the most intense things she’d seen lately.

She heard soft, shuffling footsteps enter the common room, and turned her head to spot Fuuka entering then stopping with a quizzical look on her face.

“They’re playing chess,” Yukari said, answering the unasked question.

“I... can see that,” Fuuka replied, moving over to her side. “Why?”

“Junpei’s idea. Labrys found the set and Junpei asked if she knew how to play. She said she had, uh, some kind of program in her code? Like, to play chess?”

“Oh, you mean chess engines,” Fuuka replied, nodding her head. “I’ve read about those. They’re computer programs designed to play and analyze chess as efficiently as possible. I think they’ve made them so well they can beat real-life grandmasters.” Fuuka looked over at the two android sisters. “So, both of them have chess engines?”

Yukari scratched her scalp absently. “I guess so? Junpei just dragged me in here and told me they were playing then disappeared. Like he does.”

“I... see.”

“And I haven’t left because, well, look at them.”

The sisters sat at the dining table. Aigis was white, Labrys black. Aigis’s legs were crossed, with one hand on her chin, the other crossed under her chest. Labrys sat with her knees together, her hands on top. Their eyes bored into the chessboard with the kind of perfect stillness only something inorganic could pull off.

Yukari sat at their side, on a loveseat she had turned around.

“They haven’t moved in,” Yukari looked at the smartphone on her lap, “six minutes.”

“So they’ve just been staring at the board this entire time?”

“Yup.”

“And you’ve just been watching them?”

“...Yup.”

“Huh,” Fuuka said, then, “move over.”

Yukari slid aside and gave Fuuka enough room to sit. They watched in silence for a few moments before Fuuka spoke up again.

“They don’t seem to be very far into a game.”

“I don’t know much about chess, but I think they’ve only made four moves. It’s Aigis’s turn.”

“How long have they been playing?”

Yukari looked at her phone again. “Well, I was watching TV when Junpei pulled me over here... it was 6:15 then, so... twenty minutes?”

Fuuka turned to her. “They’ve only made four moves in twenty minutes?”

Yukari shrugged. “Androids.”

Fuuka turned back, bent over to put her elbows on her knees. “I shouldn’t be surprised. Chess engines are capable of analyzing thousands of potential moves, counter-moves, counter-counter moves... maybe even millions. They’re probably calculating every possible permutation of how this game could play, dozens of moves in advance.”

Yukari looked over, her eyes widening. “Really?”

“Like you said: androids.”

“Huh,” Yukari said, folding her arms over her chest. “Junpei explained some of it to me as he brought me here. Apparently, they’re using two different engines? Aigis’s is newer and more efficient, but Labrys has more data to pull from. Or like… look, I really don’t know.”

Aigis shifted in her seat. Both women froze. Wordlessly, Aigis lifted her hand up, plucked one of her pawns, and set it down two spaces ahead.

In response, Labrys’s head shifted slightly, but she made no other indication she acknowledged the change.

“And now the calculations begin anew,” Fuuka said. “They throw out all the permutations that didn’t include that move, and work through the rest.”

Yukari hummed.

“Do you know how strong they set the rating? Sometimes, chess engines are designed to use ratings to better compete against players of different skill levels.”

“I... think Junpei said they were as high as they were gonna go.”

“Oh,” Fuuka replied. “That’s... interesting.”

“I told you.”

The androids, oblivious or not to the running commentary, continued watching the board in stoic silence.

“You know,” Fuuka said after another few moments of waiting, “I’ve always wondered what their specifications were. How much processor power they have, how much memory, storage, that sort of thing. How much of it they’re using now.”

“I’d think a lot. They have human minds in addition to all the normal computer stuff. That has to take a lot of power.”

“I think so too. I’ve never gotten the chance to ask them.”

“Hmm,” Yukari said, noncommittally.

Both of them heard Junpei stomping into the room, and turned to look at him before he even began talking.

“Damn, they’re still playing?” he asked. “I thought they’d be done by now.”

“Where have _you_ been?” Yukari said. “You left me here twenty minutes ago.”

“I really hope we don't break their concentration...” Fuuka said softly.

“Talking to Chidori,” Junpei replied, not hearing her. “She wanted to catch up.”

“How’s she doing?” Yukari asked.

“Good. Studying fashion in France. Kinda lonely there, she says.”

“Fashion always seemed her thing.”

“Yeah.”

Another silence, as the sounds of city life drifted through the open windows, and a slight breeze caressed the room.

“So who’s winning?” Junpei asked, sitting on the sofa’s edge.

“I...” Yukari began, “have no idea.”

“I think it’s still too early to tell,” Fuuka said. “They’re only a few moves in.”

Labrys, not noticing or caring that Junpei had arrived, lifted up one of her bishops.

“She just took Aigis’s horse!” Yukari said. “Er. What’s that piece called?”

“Knight,” Fuuka replied.

“Right. The one that moves in that weird way.”

Aigis, meanwhile, had crossed her arms.

“Did she always look that intense before?” Junpei asked.

The room was silent enough that they perceived, on the edge of their hearing, the sound of something whirring in higher and higher frequency. Then the gears on the side of Aigis’s head began to spin.

“She... just went into Orgia Mode,” Yukari said. “Can... can she do that?”

“She never stopped being able to,” Fuuka replied, in the same incredulous tone.

“But it works outside of combat?”

“How the hell would _we_ know?” Junpei said. “Do you think it makes her better at, uh, processing?”

In another few moments, Aigis picked up her own bishop and moved it up-left four spaces. The three onlookers all turned their gaze to Labrys. They were completely silent as Aigis’s Orgia Mode mechanisms filled up the room with noise.

“Does Labrys have an Orgia Mode?” Fuuka asked.

Yukari and Junpei made unsure grunts.

Some minutes later, Labrys moved her other knight up. Almost instantly, Aigis took it with a pawn. Labrys moved her queen. Aigis castled. Labrys moved a bishop, staring down Aigis' king.

“I really have no idea what’s happening,” Yukari said, lost in the sudden flurry of activity, “I wish I had some kind of...”

She was interrupted by Aigis moving her hand to the board again. She touched her king, then tipped it onto its side.

“What? What does that mean?”

“It... means she concedes,” Fuuka said. “After twelve moves. Aigis let Labrys win.”

Yukari and Junpei stared at each other, but their attention was drawn back by Labrys’s sudden laughter.

“Ahahaha! That was a good game, sis!”

“Indeed it was, Sister, well done!” Aigis turned and smiled at the rest of the group. “I hope you found this an enjoyable demonstration of our skills, Junpei-kun.”

“Uh,” Junpei said.

“Er,” Yukari continued.

“It was… very interesting!” Fuuka said. “I never knew both of you had chess engines installed.”

“Yeah, one of the programmers did it,” Labrys said, running a hand through her silvery hair. “Apparently it’s supposed t’ make us think more strategically.”

“I have found studying chess to be a very helpful experience in combating Shadows,” Aigis said, her hands on her lap. “In fact, I am hoping to install engines for shogi, xiangqi, and go, as well.”

“She’s _really_ into it,” Labrys replied, grinning.

“It is important to have hobbies, Sister!”

“Wait, wait, wait,” Yukari said, holding a hand to her forehead. “Something’s bothering me. Why did you concede the match, Aigis? You were only twelve moves in, you had a whole entire game to play.”

“Yeah!” Junpei added.

“It is simple, Yukari-chan,” Aigis said. “I had already lost.”

“You... what?”

“As Fuuka-chan said, Sister and I predicted the entire game in advance. It so happened that she had played so well that there was no logical way for me to win. Knowing her capabilities and knowledge of chess strategy, the best outcome I saw for myself was a stalemate. As I assumed that would not be interesting for you all to watch, I conceded the game.”

“I think you could’ve done better than that, sis!” Labrys said, patting Aigis's shoulder. “You had _some_ strategies.”

“You are a very gracious winner, Sister.”

“Hehe.”

“So you heard everything we were sayin’?” Junpei said.

“Of course,” Aigis replied. “Our auditory sensors did not simply power off while we were playing. By the way, I am glad to know Chidori-chan is doing well!”

“Oh. Ha. Well. Great. That’s... great.”

Labrys looked between them, her eyes narrowing in confusion. “Who’s Chidori?”

“She’s uh...”

“She’s his girlfriend,” Yukari said flatly.

“Yukari!”

“We all know it, idiot!”

“But that’s not for you to go sayin’, like, out loud!”

“What am I supposed to do, _whisper_ it to her?!”

As they argued, as they always did, Aigis moved closer to Labrys.

“It is a very long story,” she muttered. “Perhaps I should tell it to you over another game?”

Labrys nodded, then patted Aigis’s shoulder again. “I’d like that! But this time, I wanna be white.”

“I think the handicap granted by playing as white would be quite unnecessary for you, Sister.”

“Hey, uh,” Fuuka said, sidling up to them, “how about speed chess this time?”

**Author's Note:**

> So it probably doesn't make much sense that Aigis would throw the game so quickly if she's running off a chess engine, which would normally just keep running until the end. I figure that's the human part of her taking that input and figuring out it's better to just throw the game and do something else. There's probably something about the meeting of computer programming and human intuition in there.
> 
> Mostly I just think it's funnier this way.


End file.
